docs: def dispatch(self, request, *args, **kwargs):
          ''' Get the set of invoices for which to permit notifications '''
  
          if 'pk' in self.kwargs:
              try:
                  self.invoices = Invoice.objects.filter(pk=self.kwargs.get('pk'))[:]
              except ValueError:
                  raise Http404()
              if not self.invoices:
                  raise Http404()
          else:
              ids = request.GET.get('invoices', '')
              try:
                  self.invoices = Invoice.objects.filter(id__in=[x for x in ids.split(',')])[:]
              except ValueError:
                  return HttpResponseBadRequest(_('Invalid invoice identifiers specified.'))
  
          if not self.invoices:
              return HttpResponseBadRequest(_('No invoice identifiers specified.'))
  
          toNotify = []
          cannotNotify = []
  
          for invoice in self.invoices:
              if invoice.get_default_recipients():
                  toNotify.append(invoice)
              else:
                  cannotNotify.append(invoice)
          self.toNotify = toNotify
          self.cannotNotify = cannotNotify
  
          return super(InvoiceNotificationView, self).dispatch(request, *args, **kwargs)